[Atypical epithelial hyperplasia of the breast: current state of knowledge and clinical practice]

The diagnosis of atypical epithelial hyperplasia (AEH) increases with breast cancer screening. AEH is divided in three groups: atypical ductal hyperplasia, columnar cell lesions with atypia, lobular neoplasia. The management of women with AEH is not consensual because of uncertainty about their diagnosis related to the type of the biopsy sampling (core needle biopsy or surgical excision) and their controversial clinical signification between risk marker and true precursor of breast cancer.

A systematic review of published studies was performed. Medline baseline interrogation was performed with the following keywords: atypical ductal hyperplasia, columnar cell lesions with atypia, lobular neoplasia, core needle biopsy, breast cancer, precursor lesion, hormonal replacement therapy. For each breast lesion, identified publications (English or French) were assessed for clinical practise in epidemiology, diagnosis and patient management.

With immunohistochemistry and molecular studies, AEH seems to be precursor of breast cancer. But, epidemiological studies show low rate of breast cancer in women with AEH. AEH were still classified as risk factor of breast cancer.

Because of high rate of breast cancer underestimation, surgical excision is necessary after the diagnosis of AEH at core needle biopsy. Surgical oncology rules and collaboration with radiologist are required for this surgery. A second operation was not required due to involved margins by AEH (except with pleiomorphic lobular neoplasia) because local control of breast cancer seems to be unchanged. Besides, hormonal replacement therapy for patient with AEH is not recommended because of lack of studies about this subject.